The Standard & Poor’s 500 Index lost 1.2 percent to 1,942.62 at 4 p.m. in New York, trimming a decline in the final hour after falling as much as 1.9 percent. It’s the third drop in four days, sending the gauge to a two-week low. A gauge of volatility posted its biggest gain in a month.

Equities got a boost Monday after a quartet of Fed officials talked up prospects for higher interest rates in 2015, just days after the central bank jolted investors by citing global market turmoil and a slowdown in China as reasons for standing pat. Their remarks suggested continued improvement in the domestic economy may overshadow concerns about global conditions.

The central bank’s bid for greater transparency about its criteria for a rate increase has left markets twitching with every economic report amid an expanding Fed checklist and conflicting U.S. data. Fed Chair Yellen said last week that policy makers would scrutinize slowing growth in China and emerging markets for risks that could spill over to the U.S.

Meanwhile, the market remains unconvinced a liftoff will take place this year after the Fed’s decision and its dovish statement. Traders are pricing in a roughly 41 percent probability of a rate increase by the Federal Open Market Committee’s December meeting, compared with 64 percent on Sept. 16 before the policy decision.

The Standard & Poor’s 500 Index lost 1.4 percent to 1,939.39 at 12:22 p.m. in New York, after rising 0.5 percent yesterday. The Dow Jones Industrial Average slid 216.33 points, or 1.3 percent, to 16,293.86. The Nasdaq Composite Index slumped 1.8 percent. A gauge of volatility was headed for its biggest gain in a month.